Association between meningioma consistency and surgical outcomes

OBJECTIVE Tumor consistency, or fibrosity, affects the ability to optimally resect meningiomas, especially with recent trends evolving toward minimally invasive approaches. The authors’ team previously validated a practical 5-point scale for intraoperative grading of meningioma consistency. The impact of meningioma consistency on surgical management and outcomes, however, has yet to be explored. This study aimed to determine associations between meningioma consistency and presenting symptoms, tumor characteristics, and postoperative outcomes. METHODS A total of 209 surgically resected meningiomas were intraoperatively assigned a consistency grade according to a previously validated 5-point scale, ranging from extremely soft, suctionable tumors (grade 1) to firm/calcified tumors (grade 5). Presenting symptoms, tumor characteristics, postoperative complications, and surgical outcomes for these patients were prospectively collected. Tumor consistency was analyzed in three categories (grades 1 and 2, grade 3, and grades 4 and 5), using ANOVA, chi-square or Fisher’s exact tests, and univariable logistic regression to evaluate associations between consistency and perioperative characteristics. RESULTS The study cohort included 209 patients, of whom 48 (23%) were males with a mean age of 55.0 ± 13.7 years. Meningioma consistency distribution was as follows: grades 1 and 2 (n = 23, 11.0%), grade 3 (n = 88, 42.1%), and grades 4 and 5 (n = 98, 46.9%). The majority of meningiomas were skull base tumors (n = 144, 68.9%). Higher-consistency tumors were associated with lower rates of gross-total resection (OR 0.24, 95% CI 0.13–0.46; p < 0.001), increased invasiveness (OR 4.73, 95% CI 1.53–14.60; p = 0.007), tumor recurrence following resection (OR 3.30, 95% CI 1.25–8.66; p = 0.016), reoperation (OR 3.08, 95% CI 1.16–8.14; p = 0.024), and increased complication rates (OR 2.08, 95% CI 1.05–4.15; p = 0.037). No significant associations were identified with preoperative symptoms, tumor size (mean 4.04 ± 1.50 cm), or duration of surgery (mean 4.26 ± 1.60 hours) (all p > 0.05). CONCLUSIONS Tumor consistency is associated with important meningioma characteristics and perioperative outcomes. A prior knowledge pertaining to meningioma consistency and tumor characteristics using advanced imaging is a priority and may provide surgeons with meaningful data to guide resection strategy and anticipate postoperative outcomes and complications.